石墨烯与金属的界面接触对电子输运影响的理论研究

项目名称： 石墨烯与金属的界面接触对电子输运影响的理论研究

项目编号： No.11204120

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 物理学I

项目作者： 刘洪梅

作者单位： 临沂大学

项目金额： 25万元

中文摘要： 对石墨烯/金属界面电阻起源的正确认识是实现其界面调控，成功设计新型石墨烯电子器件的基础。本项目利用密度泛函理论结合非平衡格林函数方法系统研究石墨烯与若干金属的界面结构特点和电子输运性质。将研究电子耦合强度、自旋极化、以及石墨烯缺陷(空穴、掺杂和氧化缺陷)对石墨烯/金属界面电子输运性质的影响。通过分析体系的结合能、能带结构、态密度、磁结构、透射谱及电流-电压关系等，阐明接触电阻对界面耦合、石墨烯构型的依赖性，揭示磁性金属和石墨烯缺陷导致的界面电子输运变化，以达到界面优化的目的，为石墨烯电子器件的设计提供物理依据。

中文关键词： 电子输运；石墨烯-金属界面；接触电阻；第一性原理；分子电子器件

英文摘要： Clear understanding of the origin of the graphene-metal contact resistance is central to the design of new graphene electronic device. In the present project, we propose to theoretically study the interfacial structure and the electron transport behavior in graphene-metal system using density functional theory and non-equilibrium green's function method. To reveal the origin of interfacial contact, we focus on the influences of key factors on electron transport in graphene-metal system, including electronic coupling of interface, spin polarization induced by magnetic metals, and defects in graphene(such as vacant defects, doping defects, and oxidation defects). From the results of binding energy, band structure, magnetic structure, density of states, transmission spectrum, and current-voltage curves, we can clarify the dependence of contact resistance on interfacial coupling and graphene structure. Then, by comparing non-magnetic metal with magnetic metal, the influence of magnetic metal on the contact resistance can be understood. Finally, we will point out the effects of various defects on geometric structure and transport behavior of graphene. To provide effective graphene-metal interfac, the metallic contact effects on electron transport through graphene are systematically investigated. The proposed research

英文关键词： electron transport；graphene-metal interface；contact resistance；first-principles theory；molecular electronics